<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/welcome' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 警告区域 -->
      <el-alert
        title="注意：只允许为第三级分类设置相关参数!"
        type="warning"
        :closable="false"
        show-icon
      >
      </el-alert>

      <!-- 选择商品分类区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 级联选择器，用来展示所有的分类 -->
          <el-cascader
            :options="cateList"
            :props="cascaderProps"
            v-model="selectedKeys"
            clearable
            @change="handleChange"
            ref="cascaderRef"
          >
          </el-cascader>
        </el-col>
      </el-row>

      <!-- tab 页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" name="many">
          <!-- 添加参数的按钮 -->
          <el-button
            type="primary"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加参数</el-button
          >
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" stripe border>
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 渲染Tag标签    -->
                <el-tag
                  v-for="(item, index) in scope.row.attr_vals"
                  :key="index"
                  closable
                  @close="handleClose(index, scope.row)"
                  >{{ item }}</el-tag
                >
                <!-- 增加新的tag标签 -->
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button
                  v-else
                  class="button-new-tag"
                  size="small"
                  @click="showInput(scope.row)"
                  >+ New Tag</el-button
                >
              </template>
            </el-table-column>
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column
              label="参数名称"
              prop="attr_name"
            ></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  type="primary"
                  icon="el-icon-edit"
                  size="mini"
                  @click="showEditDialog(scope.row.attr_id)"
                  >编辑</el-button
                >
                <el-button
                  type="danger"
                  icon="el-icon-delete"
                  size="mini"
                  @click="removeParam(scope.row.attr_id)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加属性的按钮 -->
          <el-button
            type="primary"
            :disabled="isBtnDisabled"
            @click="addDialogVisible = true"
            >添加属性</el-button
          >
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData" stripe border>
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 渲染Tag标签    -->
                <el-tag
                  v-for="(item, index) in scope.row.attr_vals"
                  :key="index"
                  closable
                  @close="handleClose(index, scope.row)"
                  >{{ item }}</el-tag
                >
                <!-- 增加新的tag标签 -->
                <!-- 输入的文本框 -->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button
                  v-else
                  class="button-new-tag"
                  size="small"
                  @click="showInput(scope.row)"
                  >+ New Tag</el-button
                >
              </template>
            </el-table-column>
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column
              label="属性名称"
              prop="attr_name"
            ></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button
                  type="primary"
                  icon="el-icon-edit"
                  size="mini"
                  @click="showEditDialog(scope.row.attr_id)"
                  >编辑</el-button
                >
                <el-button
                  type="danger"
                  icon="el-icon-delete"
                  size="mini"
                  @click="removeParam(scope.row.attr_id)"
                  >删除</el-button
                >
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数的对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%"
      @close="addDialogClosed"
    >
      <!-- 表单内容 -->
      <el-form
        :model="addForm"
        :rules="addFormRules"
        ref="addFormRef"
        label-width="100px"
      >
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数的对话框 -->
    <el-dialog
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%"
      @close="editDialogClosed"
    >
      <!-- 表单内容 -->
      <el-form
        :model="editForm"
        :rules="addFormRules"
        ref="editFormRef"
        label-width="100px"
      >
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      // 商品分类数据列表
      cateList: [],
      // 选中的三级分类的Id
      selectedKeys: [],
      // 指定级联选择器的配置对象
      cascaderProps: {
        expandTrigger: 'hover',
        checkStrictly: true,
        value: 'cat_id',
        label: 'cat_name',
        children: 'children',
      },
      // 表示当前展示的是哪一个 tabs 标签页
      activeName: 'many',
      // 动态参数的数据
      manyTableData: [],
      // 静态属性的数据
      onlyTableData: [],
      // 控制添加参数对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据对象
      addForm: {
        attr_name: '',
      },
      // 添加表单的验证规则对象
      addFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' },
        ],
      },
      // 控制修改参数对话框的显示与隐藏
      editDialogVisible: false,
      // 修改参数的表单数据对象
      editForm: {},
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    // 获得商品分类数据列表
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status != 200) {
        return this.$message.error('获得商品分类数据列表失败')
      }
      this.cateList = res.data
    },
    // 实现只能选择三级分类的功能，选择其他其他级别的分类时强制清空
    handleChange() {
      this.$refs.cascaderRef.dropDownVisible = false
      this.getParamsData()
    },
    handleTabClick() {
      this.getParamsData()
    },
    // 获得商品参数
    async getParamsData() {
      if (this.selectedKeys.length != 3) {
        this.selectedKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      let id = this.selectedKeys[2]
      const { data: res } = await this.$http.get(
        `categories/${id}/attributes`,
        { params: { sel: this.activeName } }
      )
      if (res.meta.status != 200) {
        return this.$message.error('获取参数列表失败')
      }
      res.data.forEach((item) => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制输入的文本框的显示与隐藏，以实现增加新的tag标签
        item.inputVisible = false
        // 新的tag标签的内容
        item.inputValue = ''
      })
      if (this.activeName == 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    // 当关闭对话框时，清除残余的数据
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    // 添加参数
    async addParams() {
      const { data: res } = await this.$http.post(
        `categories/${this.cateId}/attributes`,
        {
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName,
        }
      )
      if (res.meta.status != 201) {
        return this.$message.error('添加参数失败')
      }
      this.$message.success('添加参数成功')
      this.getParamsData()
      this.addDialogVisible = false
    },
    // 当关闭对话框时，清除残余的数据
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },
    //展示修改参数的对话框
    async showEditDialog(attrId) {
      const { data: res } = await this.$http.get(
        `categories/${this.cateId}/attributes/${attrId}`
      )
      if (res.meta.status != 200) {
        return this.$message.error('获取参数失败')
      }
      this.editForm = res.data
      this.editDialogVisible = true
    },
    // 修改参数
    editParams() {
      this.$refs.editFormRef.validate(async (valid) => {
        if (!valid) {
          return this.$message.error('请输入新的参数名')
        }
        const { data: res } = await this.$http.put(
          `categories/${this.cateId}/attributes/${this.editForm.attr_id}`,
          {
            attr_name: this.editForm.attr_name,
            attr_sel: this.activeName,
          }
        )
        if (res.meta.status != 200) {
          return this.$message.error('修改参数失败')
        }
        this.$message.success('修改参数成功')
        this.getParamsData()
        this.editDialogVisible = false
      })
    },
    // 删除参数
    removeParam(attrId) {
      this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning',
      })
        .then(async () => {
          const { data: res } = await this.$http.delete(
            `categories/${this.cateId}/attributes/${attrId}`
          )
          if (res.meta.status != 200) {
            this.$message.error('删除失败')
          }
          this.$message.success('删除成功!')
          this.getParamsData()
        })
        .catch(() => {
          this.$message.info('已取消删除')
        })
    },
    // 展示文本框——实现添加新的tag标签页
    showInput(row) {
      row.inputVisible = true
      // $nextTick 方法的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
      this.$nextTick((_) => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    // 添加参数
    handleInputConfirm(row) {
      if (row.inputValue.trim().length == 0) {
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      this.saveAttrVals(row)
    },
    // 将参数的更改结果保存到数据库
    async saveAttrVals(row) {
      const { data: res } = await this.$http.put(
        `categories/${this.cateId}/attributes/${row.attr_id}`,
        {
          attr_name: row.attr_name,
          attr_sel: row.attr_sel,
          attr_vals: row.attr_vals.join(' '),
        }
      )
      if (res.meta.status != 200) {
        return this.$message.error('保存参数失败')
      }

      this.$message.success('保存参数成功')
    },
    // 删除参数
    handleClose(i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row)
    },
  },
  computed: {
    // 如果没有选择三级分类，禁用按钮
    isBtnDisabled() {
      if (this.selectedKeys.length != 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId() {
      if (this.selectedKeys.length == 3) {
        return this.selectedKeys[2]
      }
      return ''
    },
    // 动态计算标题的文本
    titleText() {
      if (this.activeName == 'many') {
        return '动态参数'
      }
      return '静态属性'
    },
  },
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin-top: 15px;
}

.el-cascader {
  width: 260px;
}

.el-tag {
  margin: 10px;
}

.input-new-tag {
  width: 120px;
}
</style>